1. Field of the Invention
Embodiments of the present inventive concept relate to an image forming apparatus having a developing device to reduce image defects.
2. Description of the Related Art
An image forming apparatus is designed to print an image on a recording medium based on input image signals. Examples of image forming apparatuses include printers, copiers, fax machines, and devices combining functions thereof.
Such an image forming apparatus includes a developing device to feed developer to a photoconductor drum on which an electrostatic latent image has been formed, so as to develop the electrostatic latent image into a visible image.
The developing device is divided into a developer feed unit in which developer is stored and a developing unit in which the electrostatic latent image is developed into a visible image using the developer fed from the developer feed unit.
In the above-described developing device, the developer feed unit and the developing unit may be integrated with each other, or may be separated from each other so as to be detachably attached to each other.
The developing device typically takes the form of a cartridge. Major developing elements including a photoconductor drum, charging roller, cleaning roller, developing roller and feed roller are accommodated in a main body of the developing device in the form of a single process cartridge.
Typically, prior to being mounted within the image forming apparatus, the cartridge-shaped developing device remains in a state in which nips are defined between the photoconductor drum and the charging roller and between the charging roller and the cleaning roller.
That is to say, since the charging roller is under pressure by a pressure member and thus, comes into pressure contact with the photoconductor drum, a surface of the charging roller has a nip indented by a predetermined depth.